Heating or air-conditioning system for a motor vehicle

ABSTRACT

The invention relates to a heating or air-conditioning system for a motor vehicle, by which individual zones of the vehicle interior can be supplied with separately temperature-controlled air. An improved heating or air-conditioning system, which requires just a small amount of installation space, feeds differently temperature-controlled air to a plurality of air-conditioning zones. Despite the small amount of installation space, optimum mixing of cold air and warm air takes place in the heating or air-conditioning system, with the result that the air emerging from air-outlet openings in a respective air-conditioning zone have a constant temperature over the outlet cross section.

The present application is a divisional of U.S. application Ser. No.09/121,702, filed Jul. 24, 1998, now U.S. Pat. No. 6,971,440, the entirecontents of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a heating or air-conditioning system for amotor vehicle, by means of which individual air-conditioning zones ofthe vehicle interior can be supplied with separatelytemperature-controlled air.

2. Description of the Related Art

FR 2717747 discloses an air-conditioning installation by means of whichthe air fed to the various air-conditioning zones, namely the “frontright” (passenger seat) and “front left” (driver's seat) zones and the“rear left” and “rear right” zones, can be adjusted separately. For thispurpose, the air-conditioning installation has two air-conditioningsystems, one supplying the left-hand half of the vehicle and the othersupplying the right-hand half of the vehicle. Each of theair-conditioning systems can be used to supply the front region and rearregion with differently temperature-controlled air. Thisair-conditioning installation involves very high outlay since it has twoair-conditioning systems, each with a fan, evaporator and heater andcorresponding air lines. The system is thus correspondinglycost-intensive and, as a result of the large amount of space that itrequires, can only be used in large-capacity vehicles.

DE 39 40 361 discloses an air-conditioning system by means of which fourair-conditioning zones can be supplied. In this air-conditioning system,warm air and cold air are produced and fed to each air-conditioning zonevia separate ducts. In the region of the air-outlet openings arranged inthe respective air-conditioning zone, there is provided for eachair-conditioning zone a mixing space, in which warm air and cold air canbe mixed immediately before they emerge into the vehicle interior.Although such an air-conditioning system can supply fourair-conditioning zones with just one fan, one evaporator and one heater,the air ducts require a considerable amount of installation space since,for the air supply for each air-conditioning zone, it is necessary toprovide two air ducts, which each open out into a mixing space. Afurther disadvantage is that the warm air and cold air are only mixedimmediately before they emerge from the air-outlet nozzles, with theresult that mixing is often insufficient and hot and cold air massesemerge one beside the other from an air-outlet nozzle.

U.S. Pat. No. 5,016,704 discloses a motor-vehicle air-conditioningsystem by means of which just two air-conditioning zones, namely thefront region and the rear region, can be differently air conditioned.This air-conditioning system is divided in two downstream of theevaporator. In each sub-region, an air flux regulates the quantity ofair that is heated by the heater or is routed past the heater. Warm airand cold air can mix downstream of the heater and are fed to theindividual outlet nozzles. The disadvantage with this air-conditioningsystem is that it requires a large amount of installation space and goodair mixing is not ensured. Furthermore, it is only possible for twozones to be air conditioned.

DE 44 22 120 discloses an air-conditioning system which has left/rightregulation. In order to obtain a compact design, the cold air is routedpast the heat exchanger laterally and mixed with the warm air behind theheat exchanger. Despite the already more compact design, the amount ofinstallation space required by this air-conditioning system on accountof the warm-air pivot flaps, which are located downstream of the heatexchanger and execute a pivot movement into the mixing space, isrelatively large. A further disadvantage is that optimum mixing of coldair and warm air is not ensured since, even in its open state, thewarm-air pivot flap separates the cold and warm air masses to a certainextent. Furthermore, this air-conditioning system is not suitable forsupplying more than two air-conditioning zones.

SUMMARY OF THE INVENTION

An object of the invention is to provide an improved heating orair-conditioning system which is of straightforward construction,requires just a small amount of installation space, and by means ofwhich differently temperature-controlled air can be fed to a pluralityof air-conditioning zones. Despite the small amount of installationspace, optimum mixing of cold air and warm air is to take place in theheating or air-conditioning system, with the result that the airemerging from air-outlet openings in a respective air-conditioning zoneis not in divided form, i.e., the emerging air has to have a constanttemperature over the outlet cross section.

In accordance with this and further objectives, the present inventionprovides a heating or air-conditioning system for a motor vehiclecomprising a heater for producing warm air, at least two cold-air ductswhich are routed past the heater laterally, an air-mixing space whichadjoins the heater in the direction of air flow and is divided, by atleast one partition wall, into individual mixing spaces in which air canbe mixed by air-stream control elements to a certain temperature in eachcase and, from there, can be fed to an associated air-conditioning zonevia in each case at least one air duct and via in each case at least oneair-outlet nozzle, wherein each mixing space is assigned at least two ofthe air-stream control elements of which one is provided as a cold-airflap in the cold-air duct and a second is designed as a warm-air controlelement arranged directly on an outlet side of the heater, the warm-aircontrol element having a plurality of lamellae which are arranged in themanner of a blind and, in their closed position, cover a sub-region ofthe outlet side of the heater which is assigned to the respective mixingspace.

The further objectives, features, and advantages of the invention willbecome apparent from the detailed description that follows.

BRIEF DESCRIPTION OF THE FIGURES

The invention is explained in detail hereinbelow by way of an exemplaryembodiment, with reference to the drawing, in which:

FIG. 1 is a cross-section view showing the left half, taken along lineI-I in FIGS. 2 and 3, of a heating and/or air conditioning systemaccording to the present invention.

FIG. 2 is a cross-section view showing the lower half, taken along lineII-II in FIGS. 1 and 3, of a heating and/or air conditioning systemaccording to the present invention.

FIG. 3 is a schematic cross-section view, taken along line III-III inFIGS. 1 and 2, of a heating and/or air conditioning system according tothe present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

The present invention relates to heating or air-conditioning system fora motor vehicle, having a heater (18) for producing warm air (20),having at least two cold-air ducts (26 and 28) which are routed past theheater (18) laterally in each case, and having an air-mixing space (45)which adjoins the heater (18) in the direction of flow and is divided,by at least one partition wall (46 and 48), into individual mixingspaces (50 to 56) in which air can be mixed, by air-stream controlelements (30, 32 and 36 to 42), to a certain temperature in each caseand, from there, can be fed to an associated air-conditioning zone viain each case at least one air duct (58 to 64) feeding in each case atleast one air-outlet nozzle (not shown), wherein each mixing space (50to 56) is assigned at least two of the air-stream control elements (30and 36; 30 and 38; 32 and 40; or 32 and 42) of which one is provided asa cold-air flap (30 or 32) in that the cold-air duct (26 or 28,respectively) and a second is designed as a warm-air control element(36, 38, 40, 42) arranged directly on an outlet side (34) of the heater(18), each warm-air control element (36, 38, 40, 42) having a pluralityof lamellae (44), which are known per se, arranged in the manner of ablind and, in their closed position, cover a sub-region of the outletside (34) of the heater (18) which is assigned to the respective mixingspace (50, 52, 54, 56).

In certain embodiments the air-mixing space (45) is divided into fourindividual mixing spaces (50 to 56).

In certain embodiments each cold-air duct (26 and 28) is divided in twoand each of the four cold-air ducts (26, 26′, 28, 28′) then obtainedopens out in each case into one mixing space (50, 52, 54, 56).

In certain embodiments the cold-air flaps (30, 30′, 32, 32′) are isarranged in the region of a cold-air-duct outlet (27) and, in its openposition, executes an air-directing function and deflects the cold air(16) in the direction of the warm air (20).

In certain embodiments the cold-air flap (30) is of curved form.

In certain embodiments the warm-air control elements (36 to 42) opentoward the cold-air duct (26 or 28), and the lamellae (44), in theiropen position, execute an air-directing function and deflect the warmair (20) to the side, in the direction of the cold air (16).

In certain embodiments the heater (18) has a heat exchanger (22), whichcan have drive unit coolant of a motor vehicle flowing through it, andan additional heater (24), which is arranged parallel to said heatexchanger and preferably has electric heating elements.

In certain embodiments in each case two adjacent warm-air controlelements (36 and 38) and two adjacent cold-air flaps (30 and 30′) can becoupled.

If according to the invention, each mixing space is assigned at leasttwo of the air-stream control elements, of which one is provided as acold-air flap in the cold-air duct and a second is designed as awarm-air control element arranged directly on the outlet side of theheater, it is possible for the cold-air stream and the warm-air streamto be regulated separately from one another, this permitting optimumtemperature regulation of the air in the respective mixing space.

According to the invention, the warm-air control element is constructedfrom a plurality of lamellae which are known per se (for example from DE41 19 474 hereby incorporated by reference in its entirety), arearranged in a manner of a blind and, in their closed position, cover asub-region of the outlet side of the heater which is assigned to therespective mixing space. This configuration of the warm-air controlelements can cut back on a considerable amount of installation space.Furthermore, these blind-like warm-air control elements do not, as wasthe case with the known warm-air pivot flaps, project into the mixingspace, this ensuring better mixing of the cold air with the warm airemerging from the heater.

Each mixing space is assigned a blind-like warm-air control element ofthis type, with the result that preferably four individual mixing spacescan be provided in an extremely small amount of installation space. Thismeans that the heating or air-conditioning system according to theinvention can supply four air-conditioning zones, for example driver'sarea, passenger area, and rear left and right areas.

In order that each mixing space can also be fed cold air in a separatelyadjustable manner, each of the two cold-air ducts is divided in two.

If the cold-air flap is arranged in the region of the cold-air ductoutlet, that is to say in the vicinity of the mixing space, and, in itsopen position, executes an air-directing function, the cold air mayadvantageously be deflected in the direction of the warm air, thisensuring better mixing. For this purpose, the cold-air flap ispreferably of curved form.

In the same way, it is advantageous if the warm-air control elementshave their lamellae open toward the cold-air duct, with the result thatthe lamellae, in their open position, deflect the warm air to the side,in the direction of the cold air.

For motor vehicles with low-consumption internal combustion engineswhich only produce a small amount of waste heat, it is advantageous ifin addition to a heat exchanger, which has engine coolant flowingthrough it, the heater has an additional heater, which is arrangedparallel to said heat exchanger and preferably has electric heatingelements, such as positive-temperature-coefficient (PTC) heatingelements. This means that, even during the warm-up phase of the engineor in extremely cold weather, sufficient amounts of warm air can alwaysbe fed to the vehicle interior.

If in each case two adjacent warm-air control elements can be coupled toone another, and the associated cold-air flaps can be coupled to oneanother, it is extremely simple for the inventive air-conditioningsystem for four air-conditioning zones to be made into a heating orair-conditioning system for just two air-conditioning zones. For thispurpose, all that is required is for the corresponding warm-air controlelements and cold-air flaps to be coupled, and corresponding actuatorsfor the warm-air control elements and cold-air flaps which have beencoupled on can be dispensed with. This means that the heating orair-conditioning system according to the invention can be used in veryversatile fashion and without any additional costs being incurred, thatis to say without any additional design measures or new tools, can beused both in vehicles in which there are just two air-conditioning zonesand in vehicles in which there are four air-conditioning zones.

The invention is explained in detail hereinbelow by way of an exemplaryembodiment, with reference to the drawing. The Figures are forillustrative purposes only and do not limit the scope of the invention.

An inventive heating or air-conditioning system 10, illustrated in thedrawing, has a fan (not illustrated) and an evaporator 14, arranged in ahousing 12, for producing cold air 16. Arranged downstream of theevaporator 14 is a heater 18 for producing warm air 20. The heater 18comprises a heat exchanger 22, which can have drive unit coolant of themotor vehicle flowing through it, and optionally an additional heater24, which is arranged parallel to said heat exchanger and preferably haselectric heating elements, such as PTC heating elements.

As can be seen in FIG. 2, cold-air ducts 26 and 28, which can be closedoff via cold-air flaps 30 and 32, are provided to the sides of theheater 18. The cold-air ducts 26 and 28 are preferably each divided intwo along a plane.

FIG. 1 illustrates the left half of the housing, illustrating mixingchambers, i.e., spaces, 50 and 52 and warm-air control elements 36 and38. The right half of the housing, which carries the mixing chambers 56and 54 and warm-air control elements 42 and 40, is a mirror image of theleft half.

Following in the direction of flow, warm-air control elements 36, 38,40, 42 are provided directly at an outlet side 34 of the heater 18. Eachwarm-air control element has a plurality of lamellae 44 which arearranged in the manner of a blind and, in order to form one of thewarm-air control elements, can be pivoted together in parallel via acoupling (70). In their closed position, the lamellae 44 of a warm-aircontrol element 36, 38, 40, 42 cover an associated sub-region of theoutlet side 34 of the heater 18.

An air-mixing space 45 follows the warm-air control elements 36 to 42,as seen in the direction of flow, and the warm air 20 heated in theheater 18 and the cold air 16 routed past the heater 18 in the cold-airduct 26 or 28 enters into said air-mixing space and is mixed therein,for the purpose of obtaining air at a desired temperature.

The air-mixing space 45 is divided by at least one partition wall,preferably a plurality of partition walls 46 and 48, into individualmixing spaces. Four mixing spaces 50, 52, 54 and 56 are envisioned inthe exemplary embodiment. Each of the mixing spaces 50 to 56 is assignedone of the warm-air control elements 36 to 42, and one of the fourcold-air ducts opens out into each of the mixing spaces 50 to 56. Thecold-air ducts 26 and 28 are thus each divided into two cold-airsub-ducts along the section line II-II, it being possible for each ofthe cold-air sub-ducts to be closed off by one of the cold-air flaps 30or 32. All the flaps, that is to say the four warm-air control elementsand the four cold-air flaps, can be activated separately via a controlunit. This means that the air temperature in each mixing space can beadjusted separately, with the result that differenttemperature-controlled air can be fed to four air-conditioning zones.

The cold-air flaps 30 and 32 are preferably arranged at a cold-air-ductoutlet 27. In this case, the cold-air flaps 30 and 32 can execute anair-directing function and can deflect, in the direction of the warm air20 passing through the warm-air control elements 36 to 42, the cold air16 entering into the respective mixing space. This effect is enhanced bythe cold-air flap preferably being of curved form, as is shown in FIG. 2for the cold-air flap 30. In the same way, the warm air 20 is deflectedin the direction of the incoming cold air 16 by the lamellae 44 of thewarm-air control elements 36 to 42 opening to the side, that is to saytoward the cold-air duct 26 or 28, and, in their open position, beinginclined in the direction of the cold-air duct 26 or 28, as is shown inFIG. 2.

Air-directing ducts 58 to 66 branch off from the mixing spaces 50 to 56and each route the mixed, temperature-controlled air to outlet nozzles(not illustrated) located in the corresponding air-conditioning zones.

Above the heater 18, via a bypass 68 (FIG. 1), cold air can be fed, viathe air ducts 62 and 64, directly to a central nozzle and side nozzle,which are provided in the instrument panel.

In a further exemplary embodiment (which is not illustrated), adjacentwarm-air control elements, for example those which control the warm airfor the front and rear areas, that is to say the warm-air controlelements 36 and 38, can be coupled to one another. At the same time, theadjacent cold-air flaps of the cold-air sub-ducts of the cold-air duct26 or 28 can be coupled to one another. The coupled warm-air controlelements and cold-air flaps then need to be driven by just one actuatorin each case. With coupling of this type, the heating orair-conditioning system according to the invention can only be used forleft/right regulation.

Although only a few exemplary embodiments of this invention have beendescribed in detail above, those skilled in the art will readilyappreciate that many modifications are possible in the exemplaryembodiments without materially departing from the teachings andadvantages of this invention. Accordingly, all such modifications areintended to be included within the scope of this invention.

1. A heating or air-conditioning system for a motor vehicle, comprising:a housing; a heater that produces warm air situated within the housing,wherein the heater is located centrally within the housing and occupiesthe entire area within an outer periphery having a first lateral sideand a second lateral side opposite to said first lateral side; first andsecond cold-air ducts formed in the housing, the first cold air ductlocated on said first lateral side and the second cold air duct locatedon said second side of the heater outer periphery, the cold-air ductsbeing configured to channel air into separate air streams that are eachrouted laterally around a different one of said opposed lateral sides ofthe outer periphery of the heater and each cold-air duct having anassociated cold-air flap that controls air flow therethrough; andpartition walls within the housing, the partition walls forming fourindependent air-mixing chambers downstream of the heater in a directionof air flow, each individual mixing chamber including a warm-air controlelement that controls air flow therethrough and an air duct that feedsto an associated heating/air-conditioning zone, wherein the warm-aircontrol element includes a plurality of moveable lamellae movablebetween an open position and a closed position to block heated air fromthe heater, one of the partition walls dividing each of the cold airducts into two separate cold air ducts, to define four independent coldair ducts with each cold air duct communicating with one of the airmixing chambers and having said associated cold air flap therein.
 2. Aheating or air-conditioning system as claimed in claim 1, wherein thecold-air flap is arranged at a mouth of the respective cold-air duct,and movable between an opened position and a closed position, thecold-air flap deflecting cold air toward warm air exiting the heaterinto the respective air-mixing chamber in its open position.
 3. Aheating or air-conditioning system as claimed in claim 2, wherein thecold-air flap is curved.
 4. A heating or air-conditioning system asclaimed in claim 1, wherein the lamellae of each warm-air controlelement in their open position deflect warm air laterally toward coldair entering the air-mixing chamber from the respective cold air duct.5. A heating or air-conditioning system as claimed in claim 1, whereinthe four heating/air-conditioning zones comprise a front driver side, afront passenger side, a rear right passenger side and a rear leftpassenger side of a vehicle.
 6. A heating or air-conditioning system asclaimed in claim 1, wherein the heater includes at least a heatexchanger adapted to have drive unit coolant of a motor vehicle flowingthrough it.
 7. A heating or air-conditioning system as claimed in claim6, wherein the heater further includes an additional heater arrangedparallel to the heat exchanger.
 8. A heating or air-conditioning systemas claimed in claim 7, where the additional heater includes at least oneelectric heating element.
 9. A heating or air-conditioning system asclaimed in claim 1, wherein each cold-air duct is formed between one ofsaid lateral sides and an interior surface of the housing.
 10. A heatingor air-conditioning system for a motor vehicle, comprising: a housing; aheater that produces warm air situated within the housing, wherein theheater is located centrally within the housing and occupies the entirearea within an outer periphery having a first lateral side and a secondlateral side opposite to said first lateral side; first and secondcold-air ducts formed in the housing, the first cold air duct located onsaid first lateral side and the second cold air duct located on saidsecond side of the heater outer periphery, the cold-air ducts beingconfigured to channel air into separate air streams that are each routedlaterally around a different one of said opposed lateral sides of theouter periphery of the heater and each cold-air duct having anassociated cold-air flap that controls air flow therethrough; andpartition walls within the housing, the partition walls forming fourair-mixing chambers downstream of the heater in a direction of air flow,each individual mixing chamber including a warm-air control element thatcontrols air flow therethrough and an air duct that feeds to anassociated heating/air-conditioning zone, wherein the warm-air controlelement includes a plurality of moveable lamellae movable between anopen position and a closed position to block heated air from the heater.11. A heating or air-conditioning system as claimed in claim 10, whereinone of the partition walls divides each of the cold air ducts into twoseparate cold air ducts, to define four independent cold air ducts witheach cold air duct communicating with one of the air mixing chambers andhaving said associated cold air flap therein.
 12. A heating orair-conditioning system as claimed in claim 11, wherein the cold-airflap is arranged at a mouth of the respective cold-air duct, and movablebetween an opened position and a closed position, the cold-air flapdeflecting cold air toward warm air exiting the heater into therespective air-mixing chamber in its open position.
 13. A heating orair-conditioning system as claimed in claim 11, wherein the fourheating/air-conditioning zones comprise a front driver side, a frontpassenger side, a rear right passenger side and a rear left passengerside of a vehicle.
 14. A heating or air-conditioning system as claimedin claim 10, wherein each cold-air duct is formed between one of saidlateral sides and an interior surface of the housing.
 15. A heating orair-conditioning system for a motor vehicle, comprising: a housing; aheater that produces warm air situated within the housing, wherein theheater is located centrally within the housing and occupies the entirearea within an outer periphery having a first lateral side and a secondlateral side opposite to said first lateral side; first and secondcold-air ducts formed in the housing, the first cold air duct located onsaid first lateral side and the second cold air duct located on saidsecond side of the heater outer periphery, the cold-air ducts beingconfigured to channel air into separate air streams that are each routedlaterally around a different one of said opposed lateral sides of theouter periphery of the heater and each cold-air duct having anassociated cold-air flap that controls air flow therethrough; and atleast one partition wall within the housing, the partition walls formingair-mixing chambers downstream of the heater in a direction of air flow,each individual mixing chamber including a warm-air control element thatcontrols air flow therethrough and an air duct that feeds to anassociated heating/air-conditioning zone, wherein the warm-air controlelement includes a plurality of moveable lamellae movable between anopen position and a closed position to block heated air from the heater,wherein the lamellae of each warm-air control element in their openposition are oriented to be partially open so as to deflect warm airlaterally toward cold air entering the air-mixing chamber from therespective cold air duct.
 16. A heating or air-conditioning system asclaimed in claim 15, wherein each cold-air duct is formed between one ofsaid lateral sides and an interior surface of the housing.